/*
 * libid3tag - ID3 tag manipulation library
 * Copyright (C) 2000-2004 Underbit Technologies, Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * $Id: debug.c,v 1.8 2004/01/23 09:41:32 rob Exp $
 */

# ifdef HAVE_CONFIG_H
#  include "config.h"
# endif

# include "global.h"

# undef malloc
# undef calloc
# undef realloc
# undef free

# include <stdio.h>
# include <stdlib.h>
# include <string.h>

# include "debug.h"

# if defined(DEBUG)

# define DEBUG_MAGIC    0xdeadbeefL

struct debug
{
    char const   *file;
    unsigned int line;
    size_t       size;
    struct debug *next;
    struct debug *prev;
    long int     magic;
};

static struct debug *allocated;
static int          registered;

static
void check(void)
{
    struct debug *debug;

    for (debug = allocated; debug; debug = debug->next)
    {
        if (debug->magic != DEBUG_MAGIC)
        {
            fprintf(stderr, "memory corruption\n");
            break;
        }

        fprintf(stderr, "%s:%u: leaked %lu bytes\n",
                debug->file, debug->line, debug->size);
    }
}

void *id3_debug_malloc(size_t size, char const *file, unsigned int line)
{
    struct debug *debug;

    if (!registered)
    {
        atexit(check);
        registered = 1;
    }

    if (size == 0)
        fprintf(stderr, "%s:%u: malloc(0)\n", file, line);

    debug = malloc(sizeof(*debug) + size);
    if (debug == 0)
    {
        fprintf(stderr, "%s:%u: malloc(%lu) failed\n", file, line, size);
        return 0;
    }

    debug->magic = DEBUG_MAGIC;

    debug->file = file;
    debug->line = line;
    debug->size = size;

    debug->next = allocated;
    debug->prev = 0;

    if (allocated)
        allocated->prev = debug;

    allocated = debug;

    return ++debug;
}

void *id3_debug_calloc(size_t nmemb, size_t size,
                       char const *file, unsigned int line)
{
    void *ptr;

    ptr = id3_debug_malloc(nmemb * size, file, line);
    if (ptr)
        memset(ptr, 0, nmemb * size);

    return ptr;
}

void *id3_debug_realloc(void *ptr, size_t size,
                        char const *file, unsigned int line)
{
    struct debug *debug, *new;

    if (size == 0)
    {
        id3_debug_free(ptr, file, line);
        return 0;
    }

    if (ptr == 0)
        return id3_debug_malloc(size, file, line);

    debug = ptr;
    --debug;

    if (debug->magic != DEBUG_MAGIC)
    {
        fprintf(stderr, "%s:%u: realloc(%p, %lu) memory not allocated\n",
                file, line, ptr, size);
        return 0;
    }

    new = realloc(debug, sizeof(*debug) + size);
    if (new == 0)
    {
        fprintf(stderr, "%s:%u: realloc(%p, %lu) failed\n", file, line, ptr, size);
        return 0;
    }

    if (allocated == debug)
        allocated = new;

    debug = new;

    debug->file = file;
    debug->line = line;
    debug->size = size;

    if (debug->next)
        debug->next->prev = debug;
    if (debug->prev)
        debug->prev->next = debug;

    return ++debug;
}

void id3_debug_free(void *ptr, char const *file, unsigned int line)
{
    struct debug *debug;

    if (ptr == 0)
    {
        fprintf(stderr, "%s:%u: free(0)\n", file, line);
        return;
    }

    debug = ptr;
    --debug;

    if (debug->magic != DEBUG_MAGIC)
    {
        fprintf(stderr, "%s:%u: free(%p) memory not allocated\n", file, line, ptr);
        return;
    }

    debug->magic = 0;

    if (debug->next)
        debug->next->prev = debug->prev;
    if (debug->prev)
        debug->prev->next = debug->next;

    if (allocated == debug)
        allocated = debug->next;

    free(debug);
}

void *id3_debug_release(void *ptr, char const *file, unsigned int line)
{
    struct debug *debug;

    if (ptr == 0)
        return 0;

    debug = ptr;
    --debug;

    if (debug->magic != DEBUG_MAGIC)
    {
        fprintf(stderr, "%s:%u: release(%p) memory not allocated\n",
                file, line, ptr);
        return ptr;
    }

    if (debug->next)
        debug->next->prev = debug->prev;
    if (debug->prev)
        debug->prev->next = debug->next;

    if (allocated == debug)
        allocated = debug->next;

    memmove(debug, debug + 1, debug->size);

    return debug;
}

# endif
